LOS ANGELES >> Big surf kept rolling ashore Monday along south-facing sections of the Southern California coast after bodysurfers challenged the towering waves over the weekend and lifeguards were kept busy pulling people from the water.

The highest surf was expected Monday, with some sets up to 12 feet along beaches in Orange and San Diego counties and 10 feet at Malibu and Zuma in Los Angeles County, the National Weather Service said.

By midmorning, 6- to 8-foot waves were reported at Santa Monica. The surf was slighter higher in Venice, forecasters said.

Cloudy weather kept crowds at bay at Newport Beach, which saw 55,000 visitors over the weekend. Even so, more lifeguards were on duty Monday than usual because of the expected surf, said Newport Beach Chief Lifeguard Rob Williams.

The rough conditions extended north along the coast to San Luis Obispo County. Avalon, Port San Luis, San Simeon and Cayucos could see currents capable of dislodging moored vessels and docks, forecasters said.

“Inexperienced swimmers should definitely stay out of the water,” Seal Beach police Sgt. Ron LaVelle said.

Lifeguards pulled 17 people out of the water over the weekend off Newport Beach, home of the Wedge, a famous surfing spot. It was the busiest weekend for lifeguards since March when 134 people were rescued during a weekend of big waves and warm weather.

The high tides have been caused by a Southern Hemisphere storm.

The conditions caused minor flooding Sunday night along beachfront homes in low-lying Seal Beach. Water washed up over the boardwalk, but there was no property damage,

Lifeguards were filling sandbags on Monday and planned to dig trenches to divert water from the lowest spots of the beach.

Big waves along the Southern California coast on Sunday forced a cruise ship to change course.

The Carnival Imagination was forced to dock in San Diego because the high surf and long swells in Long Beach could make it unsafe to keep a ship’s gangway connected and potentially stress the ship’s mooring lines, Carnival Cruise Lines said in a statement.

“Therefore, in the interest of caution, the cruise ship … deviated to San Diego,” the statement said.

Passengers scheduled to sail on the next cruise were bused from Long Beach to San Diego.